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<jats:p>Indium selenide, a III–V group semiconductor with layered structure, attracts intense attention in various photoelectric applications, due to its outstanding properties. Here, we report super deformability and thermoelectricity of <jats:italic>γ</jats:italic>-InSe single crystals grown by modified Bridgeman method. The crystal structure of InSe is studied systematically by transmission electron microscopy methods combined with x-ray diffraction and Raman spectroscopy. The predominate phase of <jats:italic>γ</jats:italic>-InSe with dense stacking faults and local multiphases is directly demonstrated at atomic scale. The bulk <jats:italic>γ</jats:italic>-InSe crystals demonstrate surprisingly high intrinsic super deformative ability which is highly pliable with bending strains exceeding 12.5% and 264% extension by rolling. At the meantime, InSe also possesses graphite-like features which is printable, writable, and erasable. Finally, the thermoelectric properties of <jats:italic>γ</jats:italic>-InSe bulk single crystals are preliminary studied and thermal conductivity can be further reduced via bending-induced defects. These findings will enrich the knowledge of structural and mechanical properties’ flexibility of InSe and shed lights on the intrinsic and unique mechanical properties of InSe polytypes.</jats:p>

<jats:p>The development of blue semiconductor light-emitting diodes (LEDs) has produced potential applications for Pr-doped materials that can absorb blue light, especially crystals, and we now report structure and optical properties for high-quality Pr-doped single crystals of yttria-stabilized zirconia (YSZ) grown by the optical floating zone (FZ) method. X-ray diffraction (XRD) and Raman spectroscopy showed that all of the single crystal samples were in the cubic phase, whereas the corresponding ceramic samples contained a mixture of monoclinic and cubic phases. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) spectroscopy showed that Pr was present as the Pr<jats:sup>3+</jats:sup> ion in ceramic rods and single crystals after heating to high temperatures. The absorption and photoluminescence excitation (PLE) spectra of the Pr-doped YSZ crystals measured at room temperature showed strong absorption of blue light, while their photoluminescence (PL) spectra showed five emission peaks at 565 nm, 588 nm, 614 nm, 638 nm, and 716 nm under 450 nm excitation. The optimum luminescence properties were obtained with the crystal prepared using 0.15 mol% Pr<jats:sub>6</jats:sub>O<jats:sub>11</jats:sub>, and those with higher concentrations showed evidence of quenching of the luminescence properties. In addition, the color purity of Pr-doped YSZ single crystal reached 98.9% in the orange–red region.</jats:p>

<jats:p>A high quality epitaxial Si layer by molecular beam epitaxy (MBE) on Si (001) substrates was demonstrated to fabricate a channel with low density defects for high-performance FinFET technology. In order to study the effects of fin width and crystallography orientation on the MBE behavior, a 30 nm thick Si layer was deposited on the top of an etched Si fin with different widths from 10 nm to 50 nm and orientations of 〈100〉 and 〈110〉. The result shows that a defect-free Si film was obtained on the fin by MBE, since the etching damage was confined in the bottom of the epitaxial layer. In addition, the vertical growth of the epitaxial Si layer was observed on sub-10 nm 〈100〉 Si fins, and this was explained by a kinetic mechanism.</jats:p>

<jats:p>Src SH3 protein domain is a typical two-state protein which has been confirmed by research of denaturant-induced unfolding dynamics. Force spectroscopy experiments by optical tweezers and atomic force microscopy have measured the force-dependent unfolding rates with different kinds of pulling geometry. However, the equilibrium folding and unfolding dynamics at constant forces has not been reported. Here, using stable magnetic tweezers, we performed equilibrium folding and unfolding dynamic measurement and force-jump measurement of src SH3 domain with tethering points at its N- and C-termini. From the obtained force-dependent transition rates, a detailed two-state free energy landscape of src SH3 protein is constructed with quantitative information of folding free energy, transition state barrier height and position, which exemplifies the capability of magnetic tweezers to study protein folding and unfolding dynamics.</jats:p>

<jats:p>Electron density plays an important role in determining the properties of functional materials. Revealing the electron density distribution experimentally in real space can help to tune the properties of materials. Spinel LiMn<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> is one of the most promising cathode candidates because of its high voltage, low cost, and non-toxicity, but suffers severe capacity fading during electrochemical cycling due to the Mn dissolution. Real-space measurement of electron distribution of LiMn<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> experimentally can provide direct evaluation on the strength of Mn–O bond and give an explanation of the structure stability. Here, through high energy synchrotron powder x-ray diffraction (SPXRD), accurate electron density distribution in spinel LiMn<jats:sub>2</jats:sub>O<jats:sub>4</jats:sub> has been investigated based on the multipole model. The electron accumulation between Mn and O atoms in deformation density map indicates the shared interaction of Mn–O bond. The quantitative topological analysis at bond critical points shows that the Mn–O bond is relatively weak covalent interaction due to the oxygen loss. These findings suggest that oxygen stoichiometry is the key factor for preventing the Mn dissolution and capacity fading.</jats:p>

<jats:p>The synapse of human brain neurons is not only the transmission channel of information, but also the basic unit of human brain learning and information storing. The artificial synapse is constructed based on the Sr<jats:sub>0.97</jats:sub>Ba<jats:sub>0.03</jats:sub>TiO<jats:sub>3 – <jats:italic>x</jats:italic> </jats:sub> (SBT) memristor, which realizes the short-term and long-term plasticity of the synapse. The experiential learning and non-associative learning behavior in accordance with human cognitive rules are realized by using the SBT-memristor-based synapse. The process of synaptic habituation and sensitization is analyzed. This study provides insightful guidance for realization of artificial synapse and the development of artificial neural network.</jats:p>

<jats:p>A radar-infrared compatible stealth surface is designed and analyzed. Without modifying the radar absorbing material (RAM), the design can theoretically achieve radar-infrared compatibility and broadband radar absorption through surface patterns and structures. A transmission-line-based model (TLM) is developed to analyze the radar absorbing performance of the surface. Optimization of the structure geometries is conducted aiming to maximize the –10 dB absorption bandwidth in 2–18 GHz. Surface with optimized structure geometries exhibits a superior absorption bandwidth, more than twice the bandwidth of the original 1.5 mm RAM slab, while maintaining a relatively low infrared emissivity.</jats:p>

<jats:p>A semi-infinite waveguide acts as a mirror and helps protect the qubit in front of it from decoherence. Here, we investigate the interference effect in an open waveguide consisting of resonators with different decay rates. We find that a lossy resonator works as a mirror and changes the effective decay rate of the other. The spontaneous radiation of qubit is related to its environment, and we can control it by arranging the lossy resonator’s position or frequency. Our approach helps improving the qubit performance, as well as the quantum gate fidelities.</jats:p>

<jats:p>Trigger characteristics of electrostatic discharge (ESD) protecting devices operating under various ambient temperatures ranging from 30 °C to 195 °C are investigated. The studied ESD protecting devices are the H-gate NMOS transistors fabricated witha 0.18-μm partially depleted silicon-on-insulator (PDSOI) technology. The measurements are conducted by using a transmission line pulse (TLP) test system. The different temperature-dependent trigger characteristics of grounded-gate (GGNMOS) mode and the gate-triggered (GTNMOS) mode are analyzed in detail. The underlying physical mechanisms related to the effect of temperature on the first breakdown voltage <jats:italic>V</jats:italic> <jats:sub>T1</jats:sub> are investigated through the assist of technology computer-aided design (TCAD) simulation.</jats:p>

<jats:p>Ultra-high-voltage (UHV) junction field-effect transistors (JFETs) embedded separately with the lateral NPN (JFET-LNPN), and the lateral and vertical NPN (JFET-LVNPN), are demonstrated experimentally for improving the electrostatic discharge (ESD) robustness. The ESD characteristics show that both JFET-LNPN and JFET-LVNPN can pass the 5.5-kV human body model (HBM) test. The JFETs embedded with different NPNs have 3.75 times stronger in ESD robustness than the conventional JFET. The failure analysis of the devices is performed with scanning electron microscopy, and the obtained delayer images illustrate that the JFETs embedded with NPN transistors have good voltage endurance capabilities. Finally, the internal physical mechanism of the JFETs embedded with different NPNs is investigated with emission microscopy and Sentaurus simulation, and the results confirm that the JFET-LVNPN has stronger ESD robustness than the JFET-LNPN, because the vertical NPN has a better electron collecting capacity. The JFET-LVNPN is helpful in providing a strong ESD protection and functions for a power device.</jats:p>